On the surface, Mikhail Gorbachev's trip to Siberia highlights a potentially menacing problem. Complaints from workers underscored that the gap between the expectations and real attainments of reform is growing to serious proportions.

But at the same time the Soviet leader's visit seems to have been carefully structured with two aims. First, to draw attention to the dramatic problems of Siberia. And second, to lay out the agenda for the coming political season.

During impromptu chats, small meetings, and even heated gripe sessions with Siberians, Mr. Gorbachev emphasized with new urgency the failure of the system to provide a decent standard of living and an acceptable level of economic growth.

The first night's television coverage on the main news program, ``Vremya,'' emphasized the negative - Krasnoyarsk's problems with pollution, housing, and bad planning. And instead of visiting one of the area's most advanced industrial plants, Gorbachev chose to visit a Krasnoyarsk factory distinguished only by its age and the gravity of its problems.

During the Soviet leader's six-week vacation, the reform effort lost momentum - a reflection both of Gorbachev's skills as a communicator and the degree to which reforms depend almost exclusively on him. He is now once again driving home the message that reform is just beginning. He told workers several times that so far ``we have only been working out what happened to this country.''

On his trip he is sounding what may be the main themes in the reform debate in coming months: deep alarm at poor social conditions and the state of agriculture, and the need to replace dependence on the center with local self-reliance.

He has also defended the cooperatives, the country's emerging private sector. He has admitted that the cooperative system needs improving. But he has stressed that the cooperative sector has to be enormously broadened so as to absorb many of the 10 to 14 million people who will have lost their jobs by the year 2000 because of economic reforms.

He himself is being as outspoken as many of the Siberian workers he has met. Soviet officials have said that the next plenary meeting of the Communist Party Central Committee will probably concentrate on agriculture. The date for the meeting has not been announced. Judging from Gorbachev's mood in Siberia, he is open to radical solutions.

When an agronomist spoke Tuesday of the ``rational norms'' of meat and fish consumption, Gorbachev interjected, ``People are laughing at your rational norms.'' When the head of a state farm told him that ``you have not seen the whole disaster, just half of it,'' Gorbachev listened without objection. He seemed interested but not shocked when the same speaker called for the voluntary dismantling of collective agriculture and the restoration of family farms.

Another key issue this winter will probably be cuts in the bureaucracy. In August, Alexander Yakovlev told interviewers that plans to cut the Central Committee staff were under discussion. He also suggested that the party's administration should be halved.

In a wide-ranging article published Wednesday in the weekly Literaturnaya Gazeta, political observer Fyodor Burlatsky went further. He wrote of cutting two-thirds of the country's 18 million bureaucrats and reducing the total number of government ministries and departments from about 100 to 15 or 20.

Mr. Burlatsky's ideas have often prefigured those of Gorbachev. While Gorbachev seems this week determined to prove the bankruptcy of the present system by examining its economic and social failures, Burlatsky was providing the historical and political background to the bankruptcy. His article was in fact the most thoroughgoing repudiation yet of former leader Leonid Brezhnev.

Burlatsky reviewed recent Soviet history, from Nikita Khrushchev (whose aide he once was) through Brezhnev and Yuri Andropov to the present. He dismissed the idea of ``two Brezhnevs'' - an early leader who favored reform, and a later one who lost interest. Until recently the idea was tacitly accepted even by the most reform-minded of top leaders. He emphasized the need for a nonauthoritarian approach to politics, where the rights of the minority were guaranteed.

Burlatsky, however, ended his article on a more practical note. Some of the unprincipled politicians of the Brezhnev years - ``our home-grown Fouch'es and Talleyrands'' - were now fighting for survival, he remarked. It may not have been a total coincidence that he chose Joseph Fouch'e and Charles Talleyrand as his examples of timeservers (both men served the French Revolution, Napoleon, and Louis XVIII). Fouch'e was chief of secret police, Talleyrand was foreign minister.

The two most prominent holdovers from the Brezhnev era are KGB security police chief Viktor Chebrikov and former Foreign Minister Andrei Gromyko.